NO. 2284. ]s[EW NORTH AMERICAN ICHNEUMON-FLIES— CUSHAIAN. 627 



pressed abdomen, and long ovipositor render the genus easily sep- 

 arable from the other genera of the Hemitelini. According to Roman 

 the bidentate clypeus is not a character of generic importance, in 

 which he is undoubtedly correct. 



The folloAving new species has the body and ovipositor even longer 

 and more slender than usual, the antennae more slender with longer 

 joints, the legs more slender, the clypeus without apical teeth, and 

 the abdomen more strongly compressed than either of the species here- 

 tofore referred to the genus. In Ashmead's key it runs best to Daictes 

 Foerster. 



ISADELPHUS EXTENSOR, new species. 



Female. — Length, G.5 mm.; antennae, 5.5 mm.; ovipositor, 8 mm. 

 Head and thorax clothed with very fine, short, appressed, cinereous 

 pubescence, vertex and temples rather full, polished, obscurely, finely 

 punctate; frons and face densely, finely punctate, pubescence of face 

 longer and more dense; clypeus polished, narrov»dy subtruncate at 

 apex Avith a narrow inflection at either side; antennae slender with 

 the first tAvo joints about five times as long as thick, the second slightly 

 longer than first and the third shorter than the first ;. mesoscutum 

 densely punctate medially, the prescutum and lateral lobes polished, 

 weakly punctate, notauli sharply, though briefly impressed; scutellum 

 sparsely punctate, polished ; pronotum sparsely punctate, striate pos- 

 teriorly; mesopleura obliquely striate, polished above; metapleura 

 sparsely punctate, polished; propodeum cariaceous above, with a 

 tendency to punctuation basally, polished, though slightly irregularly 

 roughened behind, costulae present though very Aveak, other carinae 

 laterad of the median carinae obsolete, areola hexagonal, about as 

 broad as long, fully tAvice as wide at apex as at base; abdomen very 

 slender, strongly compressed beyond second tergite; first three ter- 

 gites granulate, others polished, first nearly tAvice as long as wide at 

 apex, its sides slightly outwardly arcuate, Avithout dorsal carinae, but 

 with broad, Aveak ridges reaching to aj)ex, spiracles only slightly be- 

 yond middle; hind tarsus distinctly longer than tibia, the basitarsus 

 nearly as long as remaining joints combined, last joint but little longer 

 than the fourth, the two combined barely longer than the third. 



Black; antennae brownish toAvards apex; mandibles reddish; palpi 

 fuscous; tegulae whitish; Aving hyaline, veins and stigma brown; 

 legs bright rufo-testaceous, hind tibiae at apex slightly and all tarsi 

 infuscate. 



Type-locality. — Palo Alto, California. 



r?/7?d.— Cat. No. 21632, U.S.N.M. 



Described from three females collected May 11, 1917, on Quercus 

 agnfolia by F. B. Herbert. 



The two paratypes are in every way typical. 



